Return-Path: From: Jukka Rissanen To: linux-bluetooth@vger.kernel.org Subject: [PATCH v4] Bluetooth: Wrong style spin lock used Date: Wed, 29 Oct 2014 10:16:00 +0200 Message-Id: <1414570560-29904-1-git-send-email-jukka.rissanen@linux.intel.com> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Use spin_lock_bh() as the code is called from softirq in networking subsystem. This is needed to prevent deadlocks when 6lowpan link is in use. Signed-off-by: Jukka Rissanen --- Hi, this v4 adds a comment why spin_lock_bh() is needed here. Cheers, Jukka net/bluetooth/hci_core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index cb05d7f..2397623 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -4661,8 +4661,12 @@ static void hci_queue_acl(struct hci_chan *chan, struct sk_buff_head *queue, skb_shinfo(skb)->frag_list = NULL; - /* Queue all fragments atomically */ - spin_lock(&queue->lock); + /* Queue all fragments atomically. We need to use spin_lock_bh + * here because of 6LoWPAN links, as there this function is + * called from softirq and using normal spin lock could cause + * deadlocks. + */ + spin_lock_bh(&queue->lock); __skb_queue_tail(queue, skb); @@ -4679,7 +4683,7 @@ static void hci_queue_acl(struct hci_chan *chan, struct sk_buff_head *queue, __skb_queue_tail(queue, skb); } while (list); - spin_unlock(&queue->lock); + spin_unlock_bh(&queue->lock); } } -- 1.8.3.1